RESUMEN
BACKGROUND AND PURPOSE: Precision medicine is an approach to disease diagnosis, treatment, and prevention that relies on quantitative biomarkers that minimize the variability of individual patient measurements. The aim of this study was to assess the intersite variability after harmonization of a high-angular-resolution 3T diffusion tensor imaging protocol across 13 scanners at the 11 academic medical centers participating in the Transforming Research and Clinical Knowledge in Traumatic Brain Injury multisite study. MATERIALS AND METHODS: Diffusion MR imaging was acquired from a novel isotropic diffusion phantom developed at the National Institute of Standards and Technology and from the brain of a traveling volunteer on thirteen 3T MR imaging scanners representing 3 major vendors (GE Healthcare, Philips Healthcare, and Siemens). Means of the DTI parameters and their coefficients of variation across scanners were calculated for each DTI metric and white matter tract. RESULTS: For the National Institute of Standards and Technology diffusion phantom, the coefficients of variation of the apparent diffusion coefficient across the 13 scanners was <3.8% for a range of diffusivities from 0.4 to 1.1 × 10-6 mm2/s. For the volunteer, the coefficients of variations across scanners of the 4 primary DTI metrics, each averaged over the entire white matter skeleton, were all <5%. In individual white matter tracts, large central pathways showed good reproducibility with the coefficients of variation consistently below 5%. However, smaller tracts showed more variability, with the coefficients of variation of some DTI metrics reaching 10%. CONCLUSIONS: The results suggest the feasibility of standardizing DTI across 3T scanners from different MR imaging vendors in a large-scale neuroimaging research study.
Asunto(s)
Encéfalo/diagnóstico por imagen , Imagen de Difusión Tensora/normas , Neuroimagen/normas , Imagen de Difusión Tensora/métodos , Humanos , Neuroimagen/métodos , Fantasmas de Imagen , Reproducibilidad de los Resultados , VoluntariosRESUMEN
This study compared the severity of illness and outcomes of surgical intensive care unit (SICU) patients age 100 years or older with those of younger SICU patients. Severity of illness was measured with the Simplified Acute Physiology Score (SAPS) and the Quantified Therapeutic Intervention Scoring System (QTISS). Outcomes were evaluated with SICU length of stay (LOS), hospital LOS, SICU mortality, and hospital mortality. All patients admitted to an urban, tertiary-care SICU from August 1, 1986 to July 31, 1998 (12 years) were included. A total of 24,395 consecutive patients were evaluated of whom nine (0.037%) were age 100 or more. Complete outcome data were available for 13,773 patients who were divided into five groups on the basis of age: <70, 70 to 79, 80 to 89, 90 to 99, and 100 years and above. Nine centenarians were admitted to the SICU of whom one died in the SICU and another died in the hospital after SICU discharge (22.2% overall mortality). Centenarian patients had higher SAPS and QTISS on admission than patients in all other groups, although this difference was not significant because of the small number of centenarians. SICU and hospital LOS were not significantly longer for centenarians. Mortality in the SICU and hospital was significantly different across the age groups and rose with age. However, the modest 11.1 per cent SICU mortality rate in centenarians along with their LOS statistics indicate that these patients fare relatively well in surgical intensive care.
Asunto(s)
Anciano de 80 o más Años , Cuidados Críticos , Procedimientos Quirúrgicos Operativos , APACHE , Factores de Edad , Anciano , Análisis de Varianza , Distribución de Chi-Cuadrado , Cuidados Críticos/estadística & datos numéricos , Mortalidad Hospitalaria , Hospitalización/estadística & datos numéricos , Hospitales Urbanos , Humanos , Tiempo de Internación/estadística & datos numéricos , Los Angeles/epidemiología , Evaluación de Resultado en la Atención de Salud , Admisión del Paciente/estadística & datos numéricos , Estudios Prospectivos , Índice de Severidad de la Enfermedad , Procedimientos Quirúrgicos Operativos/clasificación , Procedimientos Quirúrgicos Operativos/estadística & datos numéricosRESUMEN
Rapidly recurring right pleural effusion was a disabling clinical problem in a 51-year-old woman with alcoholic cirrhosis that had not been relieved by diuretic therapy or a LeVeen shunt. By injecting technetium Tc 99m albumin aggregated into the peritoneal cavity, shunt patency and rapid flow into the pleural effusion were demonstrated. In contrast, technetium Tc 99m albumin aggregated injected injected into the pleural fluid showed no movement into the abdominal cavity. These test results predicted that pleural sclerosis would help her clinical problem but would not place the abdominal contents in jeopardy. This prediction has proved to be correct.